ABSTRACT
<p><b>BACKGROUND</b>Vulnerable plaques play an important role in the onset of sudden cardiac events and strokes. How to stabilize vulnerable plaques is still a challenge to medical science. Alprostadil is a biologically active substance with strong activity on vessel. Our study assessed the stabilizing effects of an alprostadil liposome microsphere preparation (ALMP) on vulnerable plaques in the brachiocephalic artery of apolipoprotein E (Apo E) knockout mice.</p><p><b>METHODS</b>Seventy-two male Apo E-knockout mice were fed a high-fat diet beginning at eight weeks of age. At week 17, they were divided randomly into groups for treatment with a high dose (3.6 µg×kg(-1)×d(-1)) or low dose (1.8 µg×kg(-1)×d(-1)) of an ALMP, or 0.2 ml/d normal saline (control group). The drug was administered using a micro-capsule pump. Twenty weeks after drug administration, pathological changes in the vulnerable plaques within the brachiocephalic artery were assessed, and levels of anti-mouse monocyte/macrophage monoclonal antibody (MOMA-2) and superoxide anions in the plaques were detected using immunofluorescence. The soluble intercellular adhesion molecule-1 (ICAM-1) expression was measured by ELISA, and the expression of matrix metalloproteinase-9 (MMP-9) and CD40 mRNA was measured using RT-PCR. Thrombospindin-1 (TSP-1) expression was detected using Western blotting.</p><p><b>RESULTS</b>Compared with the control group, ALMP treatment significantly reduced the plaque area in the brachiocephalic artery (P < 0.01), significantly lowered the contents of the lipid core (P < 0.01), significantly reduced the number of ruptured fibrous caps (P < 0.05), and increased the thickness of the fibrous cap and significantly reduced the incidence of intra-plaque hemorrhage (P < 0.05). ALMP treatment significantly reduced the expression of MOMA-2, superoxide anion, MMP-9, ICAM-1 and CD40 in the plaques (P < 0.01), decreased plasma ICAM-1 expression (P < 0.01), and increased the expression of TSP-1.</p><p><b>CONCLUSIONS</b>Treatment with ALMP can stabilize vulnerable plaques by inhibiting inflammation.</p>
Subject(s)
Animals , Male , Mice , Alprostadil , Chemistry , Therapeutic Uses , Enzyme-Linked Immunosorbent Assay , Inflammation , Drug Therapy , Metabolism , Pathology , Intercellular Adhesion Molecule-1 , Metabolism , Liposomes , Chemistry , Mice, Knockout , Microscopy, Fluorescence , Microspheres , Plaque, Atherosclerotic , Drug Therapy , Metabolism , Pathology , Polymerase Chain ReactionABSTRACT
<p><b>OBJECTIVE</b>To establish nonalcoholic fatty liver disease (NAFLD) in young rats, and to investigate the metabolic characteristics of these rats.</p><p><b>METHODS</b>Fifteen male and fifteen female SD rats of 3 weeks old were randomly divided into three groups, normal group (N), 20% high fat group (HF1) and 30% high fat group (HF2). All the rats were fed under Specific pathogen Free (SPF) condition for 6 weeks and executed at the end of the 6th week. Body length and weight of each rat as well as their liver weight were measured for calculating Liver Index (LI). ALT, AST, TG, TC, INS, Glu and HOMA-IR in the blood were measured. Liver tissue homogenate was prepared for detecting TG level. The liver section was stained with HE and oil red. The expression of SPEBP-1 and leptin in liver was detected by immunostaining.</p><p><b>RESULTS</b>The typical pathological change of NAFLD was found in the rats of HF groups. In HF2 group, no rats died during the experiment and the degree of fat degeneration is homogeneous. Comparing with those in N group, TC (mmol/L), liver TG (mmol/L) and ALT levels in HF2 group were significantly elevated (2.50+/-0.39 vs 1.82+/-0.43, P less than 0.01; 25.38+/-13.29 vs 12.09+/-9.59, P less than 0.01 and 69.80+/-18.22 vs 48.00+/-10.45, P less than 0.01, respectively). Comparing with those in N group, TG level in HF1 group was significantly decreased (0.17+/-0.10 vs 0.32+/-0.12, P less than 0.05), Glu level in HF1 group was significantly elevated (12.33+/-3.48 vs 8.13+/-2.53, P less than 0.05). There were no significant difference between the results of AST, INS and HOMA-IR among the groups. The expression level of SREBP-1 and leptin increased in HF groups.</p><p><b>CONCLUSION</b>NAFLD can be induced by 30% high-fat feeding for 6 weeks in young rats, high-fat feeding induces the expression of SREBP-1 and leptin expression and fat synthesis.</p>